Monte Carlo simulation of the critical behavior near the percolation threshold with invaded cluster algorithm

We used a Monte Carlo simulation of the structurally disordered three dimensional Ising model. For the systems with spin concentrations p = 0.95 ,0.8, 0.6 and 0.5 we calculated the correlation-length critical exponent ν by finite-size scaling. Extrapolations to the thermodynamic limit yield ν(0.95) = 0.705(5) ,ν(0.8) = 0.711(6),ν(0.6) = 0.736(6) and ν(0.5) = 0.744(6). These results are compatible with some previous estimates from a variety of sources. The analysis of the results demonstrates the nonuniversality of the critical behavior in the disordered Ising model.

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Critical behavior of Pr0.65Sr0.35MnO3 compound investigated by a Monte Carlo simulation

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200315 ◽

2020 ◽

Author(s):

Lhaj el Hachemi Omari ◽

Abdelmajid Lekdadri ◽

Rachid Chami ◽

El Kibir Hlil

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Ising Model ◽

Curie Temperature ◽

Critical Behavior ◽

Nearest Neighbor ◽

Magnetic Behavior ◽

Cooling Power ◽

Thermal Bath ◽

Magnetic Entropy

The critical behavior and magnetic properties of Pr0.65Sr0.35MnO3 (symbolized by PSMO) were studied using Monte Carlo simulation (MCS). The thermal bath algorithm and the Ising model in which exchange interactions via the third nearest neighbor were used to calculate the magnetic and magneto-caloric properties. The effects of temperature (T) and external magnetic field (h) on the magnetic behavior of PSMO were examined. The results show that the Curie temperature (TC) is close to the experimental value. The magnetic entropy shows a maximum value around the TC which increases linearly with the increase of the external field. The expected critical behavior of the PSMO nanoparticles was studied through the isothermal magnetization and from the Arrott plots. The obtained values are β = 0.356, γ = 1.121, and δ = 3.95. These values not so far from those reported for the 3D-Ising model. The variation of maximum magnetic entropy (∆S_m^max) and relative cooling power (RCP) around the Curie temperature were calculated; the resulting values of ∆S_m^max and those of RCP range from 3.612 and 92.7 for 1T to 6.191 and 209.9 for 5T, respectively. These results are sufficiently interesting to consider the PSMO compound as a promising candidate for magnetic refrigeration.

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Grand canonical Monte Carlo simulation of a model colloid–polymer mixture: Coexistence line, critical behavior, and interfacial tension

The Journal of Chemical Physics ◽

10.1063/1.1773771 ◽

2004 ◽

Vol 121 (7) ◽

pp. 3253-3258 ◽

Cited By ~ 91

Author(s):

R. L. C. Vink ◽

J. Horbach

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Interfacial Tension ◽

Critical Behavior ◽

Polymer Mixture ◽

Grand Canonical Monte Carlo ◽

Coexistence Line ◽

Grand Canonical

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Monte Carlo Simulation of Correlation Effects in a Random SC Alloy via Interstitialcy Mechanisms

Diffusion Foundations ◽

10.4028/www.scientific.net/df.19.35 ◽

2018 ◽

Vol 19 ◽

pp. 35-60

Author(s):

Fabian Hergemöller ◽

Nicolaas A. Stolwijk

Keyword(s):

Monte Carlo Simulation ◽

Monte Carlo ◽

Percolation Threshold ◽

Recent Progress ◽

Correlation Effects ◽

Tracer Diffusivity ◽

Jump Frequency ◽

Percolation Behavior ◽

Mobile Component ◽

Correlation Factors

In this paper some recent progress in the area of Monte Carlo simulation of diffusion via the interstitialcy mechanism in a randomly ordered binary alloy is reviewed. Topics discussed include the calculation of tracer correlation factorsfA and fBas a function of composition and jump frequency ratiowA/wBand interstitialcy correlation factors fI; which play a crucial role in the interpretation of ion-conductivity data. The percolation behavior of fI when wA ≪ wB is analysed in detail and limits of the tracer diffusivity ratios bD A/bD B for alloy compositions below thepercolation threshold are presented. Allowance for non-collinear jumps (partly) replacing concurrent collinear site exchanges leads to a reduction of diffusion correlation effects.This goes along with a shift of the diffusion percolation threshold to lower concentrations of the (more) mobile component B. Even stronger changes of mass and charge transport compared to an exclusively collinear interstitialcy scheme are observed for additional contributions of direct interstitial jumps. It is remarkable that for both extensions of interstitialcy-mediated diffusion the Haven ratio appears to be greater than unity in certain compositionranges poor in B.

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